Arc-lamp.



E. E. SAVER ARG LAMP.

APPLICATION FILED 0071.1, 1907.

Patented Sept. 21, 1909.

:i Amig HENRY E. BAVIES, F WEEAEEN HEIGHTS, 553:@,3'3'55 Applicationtiled october 13G?.

To all whom it 'may Concern:

Be it known that' l, HENRY lL. Davies, a citizen ot' the United Statesof America, residing' at lilleehawlten Heightsr` in the county of Hudsonand vtate of New Jersey, have invented certain new and useful linnn-ovements in .lere-Lamps. ot' which the following is a speciication.

My invention relates to arc lanips and particularly to arc lainps of thetype having downwardly p'rojectinn electrodes, and consists in thefeatures set t`orth in the follow ingV specification.

in the accompanying drawings in which lny invention is illustratedFigure l is a. side elevation partly in section of my lamp; Fig. 2 is across section otl the eeononiizer portion ot' the saine; Fig. 3 is across Section at right angles thereto; Fig. 4t is a cross section of thesaine showing additional. features, and Fig. 5 is a diagram ot the lainpwindings.

One of the principal objects ot niy invention is to provide vtor a lampofthe type illustrated, an etlicient eeonoinizer.

,Referring to the drawings; it will be seen that I provide the lamp withan eeonoinizer lO'which is preferably iliade ot 'material having lowheat conductivity, and consists of a- -body portion l0 through which thetips of the electrodes `ll project. into an elliptical chamber yl2toi-ined by a depending Skirty '13. This chamber is made as small as ispractieably possible and preferably should not exceed in its greatest'dimensions two and a halt times the diameter of the electrodes. lts,shortest diameter is preferably only slightly greater than the diameterofv one of the electrodes. By making the chamber of this ronstrictedsize its sides are lcept aty a very high temperature by the are, and thecomlensation ot' the vapors troni the are is thereby retarded. This isoE espe, cial advantage' when thel electrodes contain 'salts which tendto forni a solid deposit.

The retarding of the condensation of the vapors not. only has thisadvantage but it also serves to keep the vapors longer 'at the arc andthus materially decreases the conD sinuption ot' the electrode. when theelee- Speeiicaton of Letters Patent.

.the arc by the eeonoinizer.

maintained 'in its filiation Seriali No. 395,-l'l2.

trede tips are at their most advantageous' position in the chamber7 ithasbeen ascertained by actual experiment that an electrode lite 255 percent. greater than that obtained with the ordinary round econoinizer, issecured. it ia t'ound also tl at when using the ordinary carbonelectrodes the light .troni the are has an agree-able white color, thepropor tion ot blue and violet rays not being so lgreatas in arc lampsof the ordinary type. in connection with this economi/eri l propose tonee a blow magnet lll oy which the are is depressed and spread so thatit fills the entire chamber. it will be readily seen that theadvantageous results above forth may be considerably augmented hy thismeans, it desired the econoniizer may be made of sutlfieient width andprovided with recesses to receive the pole tips of the magnet ywhich, asshown in Fig. 2 are thereby proteeted troni the heet of the arc.-

By reason oi the narrowness of the are chamber the gap between the poletips of the magnet may he inode very short., particularly when protectedtroni the heat of )is the operation ot the regulating mechanism for theelectrodes is dependent upon the resistance of the are and theresistance ol the is gi'werned by tie blow magnet, the importance otthis improvement-is apparent, Through this inagg'iietio ree'ulation thearc is most eltlcient position ia the economiser.

lllhile the constrictod chamber below is highly etlieient withou .iadditional features, l prefer to completely inclose the are by adding;la globe l5 which closely surrounds the saine and is supported in theflange rl`he joint between tin globe and the shirt is made as nearly airtight possible allowing' for the expansion and contraction of thematerials employed. This globe adds another element ot' economy sincethe combustion olI the electrodes is retarded by thus cutting ott' theoxygen supply.

rl'he etliciency ot the lainp is increased by times in the are. circuit,

ill: ese-,wee

suitably iinpregnating the same with conipounds, especially oxids, oitthe metallic 1 group commonly s polren ot as the rare earths, comprisingceriuni, erhiuni., thorium, yttrinni, l etc., either siiigly or incombination. liilhen in operation the oxids in the economizer areinfluenced hy the heat and actinic radiations Jlroin the arc andthemselves emit light. rlhis l el'ect is oit course ii'icreased it theelectrode4 l are similarly impregnated, though the inipregnation ofeither electrodes or economizer l alone is advantageous. l l

ln addition to imprcgnating the ecoi'io niizer, the electrodes or bothas described, a shell lo may he added below and around the arc, which isalso impregnated with the materials mentioned. lhis shell may he usedeither with or without the surrounding globe l5. course tue eliiciencyoit the arc is still further increased hy the light radiated l from theKids in the shell. l

.in combination ivit i the econoniizer constructed described, i noveloperating mechanism Jier the electrodes is also provided.

As shown in Fig. l, the electrodes .lll are suspended in any suitablemanner at their upper ends, as hy the cords 17 which are actuated in anysuitable manner hy the rotatable spindle 18 as by passing,- around. apulley on said spindle. ln this case the cords harry a connlerweifht li)attached to the ends opposite the electrodes. 'lhe spindle 155, isactuated hy a rotary eiectroanotor 20, acting either directly on thespindle or through gears.

The motor, as employed. by ine, is at all its action depending ldirectly on the conditions therein, and it is connected so as to presentat all times to the are current-a circuit including no loose contacts.

lhe Winding ot' the stator 2l is connected in series n' i the are,presenting a con. tinuous path to the current, from one terniinal ljthrough the stator Winding, the blow magnet i4, the arc, and hack to theother terminal ll. 'the rotor circuit 2O is tap-pcd oil' 'from thestat-:ir winding at fr, passes through the rotor coils, and returns tothe main circuit at B.

lll hen no Voltage is impressed on the lamp, the electrodes tall by`gravityV until their tips come into contact, when they supportJ eachothen l When current is passed through the lamp, the motor is energized,and its rotor revolves so as to raise the electrodes. As they are drawnupward, gradually lengthening the arc, the current diminishes. Sincethetorque et the motor varies with the furrent, ywhen I this has reacheda predetermined value, the l torque becomes balanced hy the ellective lweight ot the electrodes and their supportine; devices, and ithe rotorstopsn When the electrodes hurn away so as to l turther lengthen thearc, or when t'or any other reason the resistance oit the arc rises, thecurrent, diminishing, reduces the torque of the rotor, and the Weight ofthe electrodes `causes it. to rotate so as to lower lthe electrodes.This shortens the arc until the current again becomes normal, when therotor again comes to rest. When the lamp is properly adjusted, thisfeeding action practically steady light.

llihen several. lamps el' this type are run in series, the collectiveweight ot their electrodes may balance the collective torque. el.: theirmotors, with the result that the totallarc resistance o'l the series mayhe correct while the individual arcs may vary greatly in leiigth,causing proportionate variation in light. To overcome this, a coil l,Fig. 5, arranged in n'iagnetic opposition lo the coil 21, and isconnected in shunt across the arc. its the current in this coil varieswith the voltage acr(v the arc, when this voltage reaches itspredetermined value, the inllucncc of the coil li added to the Weightoit the electrodes halances the motor. rlhus it will be seen that anyarc of a series Will maintain a dci'inite length and conselpiently, hyadjusting all lamps of a series to the same voltage, they l` `y he madeto emit the saine amount ot lilfht,

vWhile other mechanisms electrodes and raising the saine may hecinployed, the device which l have described is considered the mostsatisfactory one.

l claim as my invent-ion:

l. ln an arc lamp having a plurality ot' downwardly pointing electrodes,an econol inizer ot'- porous material having its 'walls inu'iregnatedwith a compound of a rare earth adapted to'he rendered incandescentbythe continued presence oil the are.

2. ln an are lamp, a, plurality of downwardly pointing electrodesimpregnated with a compound of a rare earth, in comlJi nation with aneconomia/ier, the inner Walls oit which are similarly impregnated,adapted to he rendered incandescent by the continued presence of theare.

:i ln an are lamp having a plurality ott ior holding the l dowi'iwardlypointing` electrodesfan econominer having` the 'Walls oi: the arechamher impregnated with a metallic salt adapted to be renderedincandescent hy the continued presence ot the arc.

4t. in an are lamp having a plurality oll downwardly pointingelectrodes, an. econo miner having the walls oli the arc chamberimpregnated with a. metallic salt adapted to he rendered incandescent hythe heat and actinic radiations ol the arc, in con'ihination withelectrodes impregnated with a metallic salt adapted to increase theaclinic radiations ot the arc.

practically continuous, Giving a Elf) fifi

l'lll 5. 'u :1n aw hunpnarc chamberthe WHHS In testimony whefeo haw/'Qsigned my 0f wnch. are nnp'egpaed wlth a metalhc 1mm@ to thisspemficatwn, m the, presence snit adupi'cd to be, rendered mcandscent byof two subscmbmg witnesses.

:u'finfn radiations of the are. i L. GROW.

